Phrynocephalus nasatus (Reptilia, Agamidae), a New Species of Toad Agama from Western China

Abstract

Among the old not sorted out collection of the Herpetological Department of ZMMU five toad agamas have been found which were characterized by an unusual structure of the nasal region. They were described as a new species Phr. nasatus Golubev et Dunayev, sp. n.
Diagnosis: distinctly bulbous nasal shields form two kidney-shaped growths on the snout. The nostril opens in the lower nasal shield and is directed sideways from the longitudinal axis and down so that it can be seen only from below. The space between the nostrils is very wide and exceeds four to five times the space from the nostril to the edge of the supralabial fold. L./L.cd. of males is 0.70 – 0.72, of the female and juvenile specimens — 0.79 – 0.80. The front part of the snout is protuberant and breaks rather sharply at its end. A row of one to four enlarged shields (the shields of young specimens are less distinct) is situated along the center of the snout from the frontal curve to the edge of the upper lip fold near the rostral shield.
Holotype (ad. male, ZMMU³ R-7614) and paratypes (ad. male, 2 juv., ZMMU R-7615) are kept in the Moscow University Zoological Museum, one paratype (ad. female, ZIK⁴ Re-18) in the Zoological Museum of the Institute of Zoology of the Ukrainian Academy of Sciences, Kiev. Lizards of these species resemble toad agamas of the theobaldi-group (especially the forsythii). From the poorly developed ribs on the subdigital lemellae and the fringe on the toes we can assume that Phr. nasatus do not live in sand. At the same time the presence of kidney-shaped growths, «peaks», covering the nostrils is evidence of active transference of substrate elements in the habitat of this toad agama. It is quite possible that the lizard lives in the zone of aeolian processing of loess particles. A study of the literature and ornithological collections of ZMMU allows us to designate the type locality: «between the Topa-Davan pass (Topa-Bell, Karadavan Ridge; 41°34’ N, 80°48’ E) and the town of Aksu (41°11’ N, 80°14’ E), Kashgaria, West China» (the word «topa», «davan», «daban», «duvan» mean «pass», «mountain ridge», «high area», respectively). The collector of these reptiles A. I. Vilkens went through this pass to Aksu in (August ?) 1882 or 1883.